Given that versions of this column will appear not just in various forms of English, but also in Mandarin, Japanese, Danish and Brazilian Portuguese, it is reassuring that the English word 'lust' translates easily into all of them. Lust is cross-cultural.

But Marmite, now owned by Unilever, isn't. Introduced over 100 years ago, this is a powerfully flavoured food product made from yeast cells, famously dividing people into those who love it and those who hate it.

In the clean technology world, solar energy is now the 'Marmite' sector, with some experts supportive, others not. The 'Marmite' company is Bloom Energy, which was just emerging from 'stealth' with its new fuel cell product when I was in California earlier this year. There was considerable excitement in the Valley, but already critics were arguing that the whole thing was being over-hyped.

All this came to mind when I was reading a fascinating new report by the Cleantech Group and the Guardian, The Global Cleantech 100. It provides a barometer of how the cleantech experts view progress to date, which privately held companies they see as most promising, and how they view future challenges.

The project is part of a wider Global Cleantech programme, jointly developed with the UK's Guardian Media Group. This includes a newspaper supplement produced and distributed by The Guardian in the UK and online, and the annual Guardian Cleantech Summit held on 23 November.

From the work done as part of the programme and elsewhere, it is clear that the sector remains enormously volatile. Of the 100 companies in the 2010 list, only 43 were in the 2009 version.

"High turnover is consistent with the relative infancy of the cleantech wave of innovation," we are told. "External forces, such as financial market sentiment and government decisions - on feed-in tariffs, subsidies and stimulus funding - can have a quick impact on fashions and fortunes."

Then there is the 'Lust List', a sub-set of the top 100 made up of companies most admired by their peers, but with none of the 60 strong expert panel giving critical views. Silver Spring Networks topped 2010's listing, and was also the highest ranking Global Cleantech 100 company. It supplies networking communication infrastructure to utilities, for advanced metering, distribution automation and demand side management.

The other companies on the list are Zipcar (car sharing services), Opower (smart grid and energy management software), Bridgelux (energy-efficient LED lighting systems) and BrightSource Energy (solar plants for utilities and industrial companies). Most people, at best, will have heard of one or two of these companies, but the sector is maturing: 63 of the top 100 are already shipping product.

The growth regions are North America (whose share of the top 100 has risen from 55% to 57%) and Asia-Pacific (up from 3% to 7%), while Europe and Israel have slipped (42% to 37%).

Big corporations are increasingly active, as investors, partners, licensees, customers and acquirers of companies. Google, General Electric, IBM, PG&E and Siemens are the most active corporate partners of this year's top 100 companies, with the smart grid the hottest area for partnerships.

But there is also a critical role for governments, in funding research and development, incentivising investment and in helping citizens see the huge potential to tackle the environmental and natural resource challenges that now face us, wherever in the world we may live - and whatever language we may speak.